Occurrence of both hydroxyl radical and surface oxidation pathways in N-doped layered nanocarbons for aqueous catalytic ozonation

doi:10.1016/j.apcatb.2019.05.008

	Occurrence of both hydroxyl radical and surface oxidation pathways in N-doped layered nanocarbons for aqueous catalytic ozonation
	Wang, Yuxian 1,3; Chen, Lulu 3; Chen, Chunmao 2; Xi, Jiaxin 3; Cao, Hongbin 1; Duan, Xiaoguang 4; Xie, Yongbing 1; Song, Weiyu 3; Wang, Shaobin 4
刊名	APPLIED CATALYSIS B-ENVIRONMENTAL
	2019-10-05
卷号	254 页码:283-291
关键词	Metal-free catalysis Catalytic ozonation Nitrogen doping Surface oxidation Density functional theory (DFT)
ISSN号	0926-3373
DOI	10.1016/j.apcatb.2019.05.008
英文摘要	Metal-free catalysts such as N-doped nanocarbons are sustainable alternatives to metal-based catalysts for the degradation of persistent organic pollutants (POPs), but cost-efficient methods are required for their large-scale synthesis. In this study, a facile and scalable strategy was established for synthesizing layered N-doped nanocarbons via the pyrolysis of beta-cyclodextrin (beta-CD) and melamine in a N-2 atmosphere. Compared with undoped pyrolyzed beta-CD, N-doping led to a 30.3-fold enhancement in the pseudo-first-order rate constant for catalytic ozonation of oxalic acid (OA), and complete degradation of 50 mg/L OA was achieved in 45 min. Apart from the specific surface area boosting from 78.9 to 16.2 m(2)/g after N doping, the OA degradation results and material characterization also suggested that quaternary N was the main active site, which was further validated by density functional theory (DFT) simulations. DFT simulations also suggested that C atoms with high charge densities adjacent to N dopants exhibited considerable potential for the catalytic dissociation of ozone. Electron paramagnetic resonance (EPR), radical quenching, and in situ Raman studies indicated occurrence of surface oxidation pathway apart from the radical-based one. Ozone on the catalyst surface was decomposed into surface-adsorbed atomic oxygen (O-ad) and free peroxide (O-2 (free)). Both *O-ad and (OH)-O-center dot, which was further evolved on the surface or in bulk solution, contributed to OA destruction. These insights into the catalytic ozonation mechanism on N-doped nanocarbons will advance their practical application to the catalytic degradation of organic pollutants.
资助项目	National Science Fund for Distinguished Young Scholars of China[51425405] ; National Natural Science Foundation of China[21606253] ; Science Foundation of China University of Petroleum, Beijing[2462016YJRC013] ; Beijing Natural Science Foundation[8172043] ; Independent Project of the State Key Laboratory of Petroleum Pollution Control, CNPC Research Institute of Safety and Environmental Technology[2017004]
WOS关键词	REDUCED GRAPHENE OXIDE ; METAL-FREE CATALYST ; OZONE DECOMPOSITION ; REACTIVE RADICALS ; CARBON NANOTUBES ; ACTIVATED CARBON ; DEGRADATION ; WATER ; PEROXYMONOSULFATE ; REDUCTION
WOS研究方向	Chemistry ; Engineering
语种	英语
出版者	ELSEVIER SCIENCE BV
WOS记录号	WOS:000472697500028
资助机构	National Science Fund for Distinguished Young Scholars of China ; National Natural Science Foundation of China ; Science Foundation of China University of Petroleum, Beijing ; Beijing Natural Science Foundation ; Independent Project of the State Key Laboratory of Petroleum Pollution Control, CNPC Research Institute of Safety and Environmental Technology
内容类型	期刊论文
源URL	[http://ir.ipe.ac.cn/handle/122111/30042]
专题	中国科学院过程工程研究所
通讯作者	Xie, Yongbing; Song, Weiyu
作者单位	1.Chinese Acad Sci, Inst Proc Engn, Div Environm Technol & Engn, Beijing 100190, Peoples R China 2.China Univ Petr, State Key Lab Petr Pollut Control, Beijing 102200, Peoples R China 3.China Univ Petr, State Key Lab Heavy Oil Proc, 18 Fuxue Rd, Beijing 102249, Peoples R China 4.Univ Adelaide, Sch Chem Engn, Adelaide, SA 5005, Australia
推荐引用方式 GB/T 7714	Wang, Yuxian,Chen, Lulu,Chen, Chunmao,et al. Occurrence of both hydroxyl radical and surface oxidation pathways in N-doped layered nanocarbons for aqueous catalytic ozonation[J]. APPLIED CATALYSIS B-ENVIRONMENTAL,2019,254:283-291.
APA	Wang, Yuxian.,Chen, Lulu.,Chen, Chunmao.,Xi, Jiaxin.,Cao, Hongbin.,...&Wang, Shaobin.(2019).Occurrence of both hydroxyl radical and surface oxidation pathways in N-doped layered nanocarbons for aqueous catalytic ozonation.APPLIED CATALYSIS B-ENVIRONMENTAL,254,283-291.
MLA	Wang, Yuxian,et al."Occurrence of both hydroxyl radical and surface oxidation pathways in N-doped layered nanocarbons for aqueous catalytic ozonation".APPLIED CATALYSIS B-ENVIRONMENTAL 254(2019):283-291.